<template>
  <div class="star" :class="starType">
    <span
      v-for="(itemClass, index) in itemClasses"
      :key="index"
      :class="itemClass"
      class="star-item"></span>
  </div>
</template>

<script>
const LENGTH = 5
const CLS_ON = 'on'
const CLS_HALF = 'half'
const CLS_OFF = 'off'

export default {
  name: 'Star',
  props: {
    size: Number,
    score: Number
  },
  computed: {
    starType () {
      return `star-${this.size}`
    },
    itemClasses () {
      let result = []
      let score = Math.floor(this.score * 2) / 2
      let hasDecimal = score % 1 !== 0
      let integer = Math.floor(score)
      for (let i = 0; i < integer; i++) {
        result.push(CLS_ON)
      }
      if (hasDecimal) {
        result.push(CLS_HALF)
      }
      while (result.length < LENGTH) {
        result.push(CLS_OFF)
      }
      return result
    }
  }
}
</script>

<style lang="stylus" scoped>
@import "~styles/mixin.styl"
.star
  font-size 0
  .star-item
    display inline-block
    background-repeat no-repeat
  &.star-48
    .star-item
      width 20px
      height 20px
      margin-right 22px
      background-size 20px 20px
      &:last-child
        margin-right 0
      &.on
        bg-image('~img/star/star48_on')
      &.half
        bg-image('~img/star/star48_half')
      &.off
        bg-image('~img/star/star48_off')
  &.star-36
    .star-item
      width 15px
      height 15px
      margin-right 6px
      background-size 15px 15px
      &:last-child
        margin-right 0
      &.on
        bg-image('~img/star/star36_on')
      &.half
        bg-image('~img/star/star36_half')
      &.off
        bg-image('~img/star/star36_off')
  &.star-24
    .star-item
      width 10px
      height 10px
      margin-right 3px
      background-size 10px 10px
      &:last-child
        margin-right 0
      &.on
        bg-image('~img/star/star24_on')
      &.half
        bg-image('~img/star/star24_half')
      &.off
        bg-image('~img/star/star24_off')
</style>
